The present application is directed to localization and/or wayfinding, and more particularly, but not exclusively, directed to the communication of visual cues to a user's portable, hand-held device to provide for localization and/or wayfinding indoors, such as inside a building.
A Global Positioning Satellite (GPS) device is typically an effective method of localization and wayfinding in outdoor environments. GPS has become commonplace in consumer life, most prominently applied to vehicle navigation, and increasingly found in mobile phone applications. A conspicuous weakness of GPS is its poor performance indoors. Typically, no connection can be made, and the mobile unit is untrackable. The value of determining one's location indoors is wide-ranging. Consider a supermarket customer looking for the dairy section, a hurried traveler lost in an airport, or a parent and child separated at the mall. Social networking services benefit, for example, by enabling indoor “meet-ups.” To address this challenge, RF-based schemes have been proposed using varieties of radio triangulation and spectral fingerprinting. Such schemes, while technically attractive, have not seen widespread adoption in places where the demand is great: supermarkets, shopping malls, airports, etc.
Triangulation operates off of radio beacons deployed within or around the indoor environment. Funding and gaining permission to install RF infrastructure is a significant obstacle to commercial deployment. Some proposals may address this shortcoming by reusing existing beacons, (e.g., wi-fi, cellular), but a typical supermarket may have only one wi-fi AP for the entire building—if any. Moreover, cell triangulation can be imprecise indoors. RF fingerprinting compares characteristics of a location's spectral content to a pre-determined map of radio signatures. While RF fingerprinting requires no infrastructure, pre-computation of radio signatures can be difficult, so considerable manual effort may be necessary in order to build the map for each new environment. Thus, there is a ongoing demand for further contributions in this area of technology.